Advanced Database Features

Answers and Descriptions:

1. Answer: Manual databases (e.g., paper records) are less efficient due to slow retrieval and prone to loss, while electronic databases are faster and more secure with backups and passwords.
   Description: Searching a filing cabinet takes time and risks damage, whereas an electronic database can instantly find data and restrict access with security features.
2. Answer: An appropriate field size (e.g., 10 characters for a name) prevents wasted space and ensures data fits correctly without truncation.
   Description: If “Name” is set to 5 characters, “Robert” would be cut to “Rober,” causing errors. A size of 20 allows flexibility without excess.
3. Answer: Mismatched data types (e.g., text instead of number for “Age”) prevent calculations or sorting, leading to errors.
   Description: If “Age” is text, you can’t calculate an average. Correcting this during conversion ensures functionality.
4. Answer: Create a “Books” table (Primary Key: Book ID) and a “Borrowers” table (Primary Key: Borrower ID, Foreign Key: Book ID) to link borrowed books to borrowers.
   Description: This setup tracks which borrower has which book, using Book ID as the foreign key to connect the tables.
5. Answer: The DBMS rejects the entry or shows an error, as relational integrity requires valid links between tables.
   Description: If a “Grades” table references a “Student ID” that doesn’t exist in the “Students” table, the system flags it to maintain data accuracy.